CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (USD $) In Millions, unless otherwise specified	Total	Total AAR Stockholders' Equity	Common Stock	Capital Surplus	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest
Balance at May. 31, 2011	$ 835.3	$ 835.9	$ 45.0	$ 423.8	$ 486.1	$ (100.4)	$ (18.6)	$ (0.6)
Increase (Decrease) in Stockholders' Equity
Net income	68.0	67.7			67.7			0.3
Cash dividends	(12.0)	(12.0)			(12.0)
Stock option activity	4.7	4.7		4.8		(0.1)
Restricted stock activity	8.8	8.8	(0.2)	(4.8)		13.8
Repurchase of shares	(3.7)	(3.7)				(3.7)
Equity portion of bond repurchase	(0.2)	(0.2)		(0.2)
Other comprehensive income, net of tax	(36.6)	(36.6)					(36.6)
Assumption of noncontrolling interest	1.7							1.7
Balance at May. 31, 2012	866.0	864.6	44.8	423.6	541.8	(90.4)	(55.2)	1.4
Increase (Decrease) in Stockholders' Equity
Net income	55.5	55.0			55.0			0.5
Cash dividends	(12.9)	(11.9)			(11.9)			(1.0)
Stock option activity	4.5	4.5		2.8		1.7
Restricted stock activity	7.8	7.8	(0.1)	4.7		3.2
Repurchase of shares	(14.6)	(14.6)				(14.6)
Equity portion of bond repurchase	0.5	0.5		0.5
Other comprehensive income, net of tax	12.7	12.7					12.7
Balance at May. 31, 2013	919.5	918.6	44.7	431.6	584.9	(100.1)	(42.5)	0.9
Increase (Decrease) in Stockholders' Equity
Net income	73.2	72.9			72.9			0.3
Cash dividends	(11.8)	(11.8)			(11.8)
Stock option activity	7.8	7.8		2.8		5.0
Restricted stock activity	(0.2)	(0.2)		2.0		(2.2)
Repurchase of shares	(1.0)	(1.0)				(1.0)
Other comprehensive income, net of tax	13.2	13.2					13.2
Balance at May. 31, 2014	$ 1,000.7	$ 999.5	$ 44.7	$ 436.4	$ 646.0	$ (98.3)	$ (29.3)	$ 1.2